I made the mistake of peering into the Code not long ago. If you are not a
technical person, an engineer say, it might as well have been written in an
obscure dialect of Urdu.
I then made the further mistake of discussing my grounding idea with my
electrician who installed the electrical service in the outbuilding now
known as my shack. We went round and round politely not understanding each
other for 20 minutes or more, before he finally said he would talk to his
suppliers in the big city and see if they had the devices he was sure were
required that he did not stock, and seldom used but cost several hundred
dollars and would require a seemingly massive installation process. Or so
I discerned from the conversation.
There seems to be no uniformity of opinion about what is required, what is
adequate, in a variety of situations hams face in planning and installing
grounding systems, except everyone seems to agree that the old
recommendation of connecting a large wire as short as possible to the water
pipe outside isn't the way to go.
I spent $475 installing an 8' copper clad rod in a pit 30" deep, 8' long
and 6" side here on the Rock Ranch. The money was spent hiring a young man
to try to dig the pit, and renting a demo hammer from HD. It was like
carving the face of Mt. Rushmore, and took him 2 and a half days working
like a rented mule. I hope it is adequate!
A volume of practical suggestions on how to approach different situations
would be worth its weight.
73 de W6OGC Jim Allen
On Sun, May 18, 2014 at 9:13 AM, Cecil <chacuff@cableone.net> wrote:
> But don't expect it to provide a clue as to how to build a ground system
> for proper lightning protection...it is concerned most about electrical
> safety grounding...important but not the all inclusive answer.
>
> Cecil
>
> Sent from my iPad
>
> > On May 17, 2014, at 3:24 PM, P C A <xtraham58@hotmail.com> wrote:
> >
> > I think everyone should start by reading the National Electrical CODE ,
> NEC on grounding, work from there. This is in part of the National Fire
> Prevention Association NFPA.Andy
> >
> >>
> >>
> >> Eric,
> >>
> >> You're the right man for the job of writing this manual. I like the
> >> lightening protection for a chapter, RF grounding for a second chapter,
> and
> >> a third on getting them both in sync.
> >>
> >> Being a sociologist by training I can appreciate the engineers
> reputation
> >> for being concise - so why not establish a drop box with the two
> chapters as
> >> a start. Open it up to everyone for reading, you take one chapter and
> >> another guy a second chapter - form a small team for each chapter with
> >> access to edit and away you go?
> >>
> >> I'll be happy to read the drafts as a non-engineer and comment
> accordingly.
> >>
> >> Kris KM2KM
> >>
> >> MERSCHROD
> >> 123 Warren Road
> >> Ithaca, NY 14850
> >> Skype: Merschrod
> >>
> >> -----Original Message-----
> >> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of R.
> Eric
> >> Sluder - W9WLW via TenTec
> >> Sent: Saturday, May 17, 2014 10:36 AM
> >> To: Discussion of Ten-Tec Equipment; Robert
> >> Subject: Re: [TenTec] Eagle problem?
> >>
> >> Ya know gentlemen; I think that some of you should gather and contribute
> >> your vast knowledge of grounding and lightening protection to establish
> a
> >> standards document that Hams can use.
> >>
> >> Imagine a standard that all Hams could reference that has been vetted by
> >> those who's credentials and industry experience provide a truly usable
> and
> >> safe reference for all.
> >>
> >> A lot of what I read is accurate, but some of it is questionable in my
> mind
> >> based on my industry training and experience in telecommunications and
> now
> >> hospital building construction. I've used IEEE, BICSI, TIA, ANSI, NEC
> and
> >> other similar references and they all collide at some point in the way
> to
> >> provide ground (earth) and lightning protection. I share all that
> because
> >> this debate has me confused at different points, and I can't imagine
> how the
> >> humble Ham who's a Dentist, truck driver or whatever their profession
> is -
> >> try to follow along and gain a general understanding of grounding and
> >> lightening protection (two different disciplines with commonality).
> >>
> >> We all could benefit (and save our stations) by some of you really
> smart and
> >> well versed chaps gathering and hammering out a standard we could all
> live
> >> and operate by.
> >>
> >> Be well, operate safely during the storm season and save your loose
> change
> >> for a Patriot. Jim Whalton gave me the run down yesterday at the TT
> >> booth... it looks like fun.
> >>
> >> 73 - Eric
> >> W9WLW
> >>
> >> On May 16, 2014 7:47:03 PM EDT, Robert <rmcgraw@blomand.net> wrote:
> >> |I had 3 pieces of 1" braid in place to bond the rotating mast to the
> >> |sleeve at the top of my tower. A lightning strike burned all 3 into.
> >> |Balled ends on the strands confirmed this.
> >> |
> >> |73
> >> |Bob
> >> |
> >> |
> >> |Sent from my iPhone
> >> |
> >> |> On May 16, 2014, at 6:04 PM, Stuart Rohre <rohre@arlut.utexas.edu>
> >> |wrote:
> >> |>
> >> |> Jim, don't we all use Flukes now? :-) I do have several at home and
> >> |work. I was remembering a discussion of a rig fault where the pin
> >> |intended for grounding, had not been grounded at the radio connector
> >> |entry to chassis.
> >> |>
> >> |> Good point you make about low ranges needed for ohms measuring.
> >> |There are some good build it yourself low ohms measuring circuits out
> >> |there, to extend the range of an ordinary meter. The Graf (author)
> >> |series of circuit diagrams books includes at least one. The ham
> >> |magazines in last 40 years had one or more.
> >> |>
> >> |> In the midst of measuring things, most good troubleshooting includes
> >> |a thorough visual inspection to see how things are bonded and grounded,
> >> |and if the circuit board is providing the connection to chassis.
> >> |> Unfortunately, we had not done a pre service inspection of the
> >> |following radio incident:
> >> |>
> >> |> For high current faults, we have seen a Yaesu 5100 that had RF
> >> |connection to circuit board and its DC negative power line to same
> >> |circuit board at other end of chassis. A lightning event on the tower
> >> |induced shield current down the coax to the radio , across the circuit
> >> |board, vaporizing part of the ground copper, and then to the DC
> >> |negative line which returned to AC third pin and power supply chassis.
> >> |>
> >> |> The bonding was done by an experienced power plant engineer, but it
> >> |provided an extra return path through that circuit board trace, that
> >> |caused severe damage to the trace. Luckily, that radio has survived
> >> |that, with a bus bar now bonding DC negative to the coax connector
> >> |shell external to the chassis. (No longer relying on the radio circuit
> >> |board traces.) The radio worked even after losing part of the board
> >> |copper, but only if the coax was connected, which was grounded to the
> >> |tower and earth providing a return through the AC third pin. That
> >> |observation prompted us to open the radio, which then showed the
> >> |missing trace.
> >> |>
> >> |> As for braid failures, literature about high current faults has
> >> |stated that braid can blow apart in a near direct strike, as little
> >> |shards of wire. Indoors in someone's shack that could cause injury, or
> >> |put small shorts into places hard to find.
> >> |>
> >> |> Copper flashing could be used in place of braid. The use or either
> >> |was to provide low inductance through wide flat conductors used for
> >> |bonding equipment together.
> >> |>
> >> |> Stuart Rohre
> >> |> K5KVH
> >> |> _______________________________________________
> >> |> TenTec mailing list
> >> |> TenTec@contesting.com
> >> |> http://lists.contesting.com/mailman/listinfo/tentec
> >> |_______________________________________________
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> >> |TenTec@contesting.com
> >> |http://lists.contesting.com/mailman/listinfo/tentec
> >>
> >> --
> >> Sent from my Android device with K-9 Mail. Please excuse my brevity.
> >> _______________________________________________
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> >>
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> >
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